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Date: Tue, 08 Apr 2003 07:26:48 -0700
From: Terry Lambert <tlambert2@mindspring.com>
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Subject: Re: SCHED_ULE question
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"Wilkinson,Alex" wrote:
> Cool, thanks for that, but what's the diff between:
> 
> #sysctl kern.quantum
> kern.quantum: 100000
> 
> AND
> 
> #sysctl kern.quntum
> sysctl: unknown oid 'kern.quntum'

You mispelled it... but it's not there in SCHED_ULE.


> What is meant to 'quantum' ?

A quantum is the longest interval that a process is allowed to
run in the presence of another ready-to-run process existing,
without voluntarily releasing the CPU for another process to
run (e.g. by making a blocking system call that doesn't result
in a threads context switch to another thread in the same
process).

It is the granularity at which some schedulers implement time
sharing.

Use a search engine to search for the independent terms:

	scheduler quantum

See also:

	lbolt

-- Terry